1. Field of the Invention
The present invention relates to a laser beam printer utilizing an electrophotography, and more particularly to a laser beam printer with no paper supply cassette.
2. Description of the Prior Art
Conventionally, such a laser beam printer utilizing an electrophotography is equipped with cassettes or trays which are mounted to one side or top of the printer, in order to accomplish the supply of papers. However, these cassettes and trays each has a specific size, resulting in limiting free selection of various sizes of papers. Due to the protruded length of such paper supply device, the length or the height of the overall construction of printer is increased, thereby causing the occupation space to increase undesirably. On the other hand, papers supplied from the paper supply device are fed into the interior of the printer, by a plurality of rollers. After passing through a developing system and a fixation part in the printer, papers are discharged from the printer by paper discharging rollers and a discharging tray. During the feeding of papers, jamming of papers in the printer often occurs. At this time, an upper frame to which the developing system and the fixation part are mounted or several cover members should be lifted for removing the jammed paper from the printer and then be returned to their original positions at which they are operatively connected to the printer, by being depressed by a strong pressure or a separate connecting device. This operation for removing jammed papers is troublesome and uneasy. Furthermore, there is a disadvantage that due to impacts and movements occurring in connecting the upper frame or cover members to the printer again, abrasion and damage of various parts and inner construction of the printer may be generated. In addition, the optical system and the developing system lost their accuracy, thereby causing print files to be badly produced and operating parts to be frequently out of order.
The discharging tray may be easily separated from the printer due to the operator's carelessness and thereby damaged. In addition, it is unfolded or taken out of the printer in printing operation, thereby causing the occupation space of overall construction to be increased.